Let's make an equation where x is the number of gallons and y will be the overall price.
2.5x=y; since it is $2.52 PER gallon, you need to multiply the amount of gallons by the cost. In this case, it is 4.
2.5(4)=10
So, the price of 4 gallons is $10.
Answer:

Step-by-step explanation:

Volume of a triangular pyramid is v=1/3AH so the answer is 8
Answer:
d + .09d
Step-by-step explanation:
9% of his salary can be found by multiplying d by 0.09. Then simply add that to his original salary to get you answer.
f-¹(x)=
Answer:
Solution given:
f(x)=
Let f(x)=y
y=
Interchanging role of x and y
x=
doing crisscrossed multiplication
x(y+7)=-2y+2
now solve it:
xy+7x=-2y+2
keep like terms in one side
xy+2y=2-7x
take common
y(x+2)=2-7x
make a value of y
y=
So,
f-¹(x)=